A fossil of Wiwaxia.
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Family: Wiwaxiidae
Genus: Wiwaxia
Walcott, 1911
  • W. corrugata
    (Matthew, 1899)
  • W. foliosa
    (Yang et al, 2014)
  • W. papilio
    (Zhang, Smith & Shu, 2015)
  • W. taijiangensis
    ( Zhao, Qian & Lee, 1994)

Wiwaxia was a genus of small, soft-bodied, mollusk-like invertebrate from the Middle Cambrian Era. It grew to be only 2 in. long and was likely the prey of animals like some small species of Anomalocaris.


Wiwaxia fossil

In 1899, G.F matthew described the first known specimen of Wiwaxia from a single spine found from its back, and several more specimens of this strange, ancient invertebrate were found when Charles Doolittle Walcott went on an expedition to the Burgess Shale in 1911. In 1966 and 1967 a paleontologist team led by a scientist by the name of Harry B. Wittington went on an expedition and found so many specimens of Wiwaxia were found that it took until 1985 to finish cleaning all of the fossils and publish a good descritption of it.



Wiwaxia is a very strange-looking invertebrate, even for most Cambrian Era animals. To the untrained eye it almost seems to appear like a kind of aquatic plant, similar to how the modern-day anemone appears. Wiwaxia was also very small, with some species growing to be only 3.4 millimeters (0.13 in.), while others could be about 50.8 mm. (2 in.) long. It was herbivorous, and mostly ate the


sludge that was found on the ocean floor.

Instead of swimming, Wiwaxia more likely trudged slowly around the bottom of the ocean trying to stay out of everyone else's way. Although small and slow, Wiwaxia was able to defend itself from predators like Opabinia with the pointy spines along its back that could grow to be as long as its body. This small but durable mollusk was soft-bodied but covered in a strange form of leaf-shaped body scales that covered its rectangular-shaped form. These are known as sclerites, and a couple other organisms like Orthrozanclus also had them.

In popular culture

Image 544 1.jpg

Wiwaxia appeared grazing with the sponges in The Burgess Shale Website on the Virtual Sea Odyssey (it was grazing some more in the Grazers video).

In the video on National Geographic called Wiwaxia it was one of the first animal showed in this video.

It also appeared in David Attenboroughs First Life.